Adaptive beam forming can be used to optimize the propagation path between a base station antenna array and a terminal such as user equipment (UE). Conventional antenna arrays have a scanning range of approximately +/−40°. Beyond that range, the scanning loss in gain may degrade propagation and also form unwanted side lobes that create interference. Furthermore, at lower frequencies (for example 3.5 GHz or 2.4 GHz), conventional antenna arrays that includes a high number of antenna elements arranged in a planar arrays can require a large physical foot print.
It is desirable to provide a planar antenna array which has the ability to cover an extended beam forming scan range of +/−(40° to 70°) in addition to a conventional scan range +/−40°.